KW26??? We had a KG84C and two KY57, and the KY was actually concidered ancient and was there for backwards compatibility with units that weren't upgraded yet.

You obviously are much younger than me. I worked on KG 13 KY 3 and KW7 which was considered portable (lots of fun carrying one up the hatch on a flying command post while it was waiting to take off ) We had 1200 baud modems that were bigger than refrigerators. I used to pray to God that **** wouldnt break during my shift. Shift registers were these big plastic modules and would provide either a 1 or 0, one per module at about an inch square apiece. A counter would consist of at least 12 of these, The good old days
When I got out of the service in 1980 I went to work for a pbx manufacturer, and couldnt believe they could run 150 phones in a box half the size of the 1200 baud modem